Impacts of social factors on free-living eating rate as assessed by multiple-pass, 24-hour recalls

Abstract

Slower eating rates have been associated with decreased food intake in laboratory settings. Free-living eating rate methods however are limited and inconsistent. This study utilized 24-hour recalls for free-living eating rate assessment and determined effects of social aspects on free-living eating behaviors using this method. Twenty-three overweight females 20±2.6 years old were recruited from a university campus. Laboratory eating rate was covertly measured during a standardized lunch on a Universal Eating Monitor (UEM). During three non-consecutive multiple-pass, 24-hour recalls, subjects provided information on meal duration, location, and people present. Free-living eating rate was calculated (kcal/min and g/min) and compared to the standard UEM. Laboratory and free-living data, meals eaten alone and socially, eating occasion type, and setting were compared using ANOVA. Free-living eating meal durations were ∼13 minutes longer (F=8.0, P<0.05), gram intake was higher (F=4.182, P<0.05), and eating rate (kcal/min) was slower (F=21.7, P<0.001) than the laboratory, when controlling for people present. There were no significant differences in kcal intake and g/min between methods. Free-living meal duration and kcal intake were higher with people present than alone (F=19.6, 13.3; P<0.001, respectively). Eating rate (kcal/min) was not significantly different, but faster in (g/min) in alone conditions than when eating with others (F=10.57; P<0.001). Eating rate results were inconsistent between laboratory and free-living assessments. There were significant differences between the two methods, though meal duration and gram intake effect sizes were not strong. Future work is needed to further develop methods to explore free-living social aspects. Free-living eating shows similar gram intake in alone and social conditions so slower eating rates are mediated by longer meal durations. Trends showed associations between social settings and greater calorie intake.^